Control for therapeutic air conditioners



Sept. 27, 1938. J. A. HEIDBRINK 2,131,103

CONTROL FOR THERAPEUTIC AIR CONDITIONERS Filed Jan. 17, 1936 Fig '1.

Patented Sept. 27, 1938 UNITED STATES PATENT OFFICE.

CONTROL FOR THERAPEUTIC AIB. CONDI- TIONERS 6 Claims. (Cl. 12S-191) My invention relates to controls for therapeutic air-conditioners, and has for its object to determine and regulate recirculation of air through the soda lime chamber and the amount of air going through the cooling chamber and from there in a closed circuit through a breathing chamber such as an oxygen tent, hood or the like, and back to the soda lime chamber.

It is well-known in therapeutic practice to provide in certain cases a breathing arrangement for a patient such that the air which he breathers may be previously treated, as, for example, by having oxygen added thereto, and such air is continuously circulated in a closed circuit. One form of such breathing arrangement is what is known as an oxygen tent, being a tent-like enclosure about the head and upper part of the body of the patient and an articial circulation of air is caused to move into and out of said enclosure. In conditioning this air, in addition to the supply of oxygen or other medicinal gases, it is necessary to remove carbon dioxide, for which reason the closed circuit of air is passed through a body of soda lime for taking out the carbon dioxide. It is also customary and desirable to cool the air in this circuit by by-passing it through a body of ice or other refrigerating coils, this cooling being particularly desirable in hot weather and in conjunction with cases wherein the patient is suffering from fever. It is, however, at times desirable to restrict the rate of flow of air or air mixture to the patient after going through the ice, as where a patient has a small tent member which substantially encloses only the head of the patient. In such cases it may also be desirable to increase the amount of travel of the gas through the soda lime solution.

It is the object of my invention to provide means for regulating from a given blower the volume of gas which passes through the cooling chamber and to the patient, and at the same time to provide means for causing a recirculation of gas through the soda lime.

'Ihe full objects and advantages of my invention will appear in connection with the'detailed description thereof, and its novel features are particularly pointed out in the claims.

In the drawing, illustrating an application of my invention in one form,-

Fig. 1 is a sectional elevation view of the soda lime and ice chamber taken on line I--I of Fig. 2. Fig. 2 is a sectional elevation view at right angles to what is shown in Fig. 1 taken on line 2-2 of Fig. 1. Fig. 3 is a sectional plan view taken on line 3--3 of Fig. 1. Fig. 4 is a fragmentary side elevation view showing the regulating control handle. Fig,v 5 is an enlarged sectional detail showing the manner of securing the damper to the damper rod.

As illustrated, an inner casing I 0 is spaced from an outer casing II and within said space is insulating material I2. A partition I3 across its narrower dimension divides this casing into an ice chamber I4 and a soda lime chamber I5. A body of ice I 6 is placed in the ice chamber or cooling chamber, or, if desired, refrigerator coils not shown may be substituted for the ice I6. As clearly shown in Fig. 1, the partition I3 does not reach to the floor of casing IIJ, but is spaced therefrom as indicated at I1. Within the soda lime chamber I5 a second partition I8 is spaced from partition I3, as indicated at I9, and termi-r nates so as to leave an opening into the top of chamber I5, as indicated at 20, and terminates at the bottom short of the iioor of casing IIJ, as indicated at 2| Within the chamber I5 is located a removable container 22 provided with reticulate walls and a reticulate` bottom wall 23, and lled With soda lime, indicated at 24. Lo. cated below the reticulate bottom 23 of the soda lime container 22, is a blower 25 which is driven by the motor. 26 controlled by switch 21. 'Ihe blower 25 is, as clearly shown in Fig. 2, positioned to draw air through the side central port 28 and discharge it through ports 29 into a bot tom chamber 30 opening through the port I'I into the bottom of ice chamber I4 and into the bottom of passageway I9. Y,

Upon a shaft 3I extending across the casings I0, II at the bottom of partition I3 is rigidly secured a damper plate 32 which swings into chamber 30 between openings I'I below partition I3 and the lower end of passageway I9, as clearly shown in Fig. 1. Upon the end of shaft 3| outside of casing Il is a handle 33 about which the shaft 3| and damper 32 are operated, and this handle cooperates with a detent scale member 34 by which the damper may be set in position to close passageway I1 or passageway I9, and in any intermediate position, as that shown in full lines in Fig. 1.

When the blower is placed in operation air is drawn through pipe 35 and port 36 into chamber I 5, whence it passes through the soda lime 24 and soda lime container 22 and through the blower and -is discharged into chamber 30. If the damper 32 is in the upper dotted-line position completely closing the opening into discharge passageway I 9,

all of this air will pass through the ice in the ice chamber f4 and through port31 and a connecting pipe to the chamber of the oxygen tent or hood, not shown, whence it will return through pipe 35 to chamber I5, thus setting up a closed circulation. If the damper 32 were dropped to the lower dotted-line position all of the air would merely be recirculated through passageway I9 and chambers I5 and 30 and the circulation through the tent or hood would stop.

If, however, the damper 32 is placed in a selected intermediate position such as that shown in full lines in Fig. 1, a part of the air from the blower 25 will go through the chamber I4 and the ice therein, and into the delivery side 31 of the closed circuit through the tent or hood and another part of said air will pass through by-pass passageway I9 and cause the gas mixture to be recirculated through the soda lime.

The advantages of this arrangement will be apparent from the foregoing description thereof. The same air-conditioning means contained in casings I0 and I I may be employed to meet different conditions of use, such as with a large tent or in very hot weather when maximum cooling and flow of air mixture in the closed circuit is required, or where a small hood is placed over the patient and a smaller amount of air mixture and less cooling is requisite. Furthermore, the recirculation through the soda lime chamber of a part of the air mixture will insure completely eilicient removal of CO2 from` the reduced air stream, giving the patient a properly purified air mixture for breathing. l The construction is very simple and adds little to the cost of the air-conditioning device, and has proved in practice to be absolutely accurate and dependable.

I claim:

1. An air-conditioner for therapeutic purposes embodying a soda lime chamber and a cooling chamber with an opening connecting said chambers, a blower adapted to establish a closed circuit of air mixture successively through the soda lime chamber and the cooling chamber, means interposed between said chambers for by-passing some of said air mixture to cause it to recirculate through the soda lime chamber, and means associated with said by-pass means for regulating the amount of the air mixture recirculated through the lime chamber. i

2. An air-conditioner for therapeutic purposes embodying a soda lime chamber and a cooling chamber with an opening connecting said chambers, a blower adapted to establish a closed circuit of air mixture successively through the soda lime chamber and the cooling chamber, and a double-walled partition y:forming a passageway opening at the top and bottom of said soda lime chamber to permit by-passing of part of said gas mixture to recirculate through the soda lime chamber.

3. An air-conditioner for therapeutic purposes embodying a soda lime chamber and a cooling chamber with an opening connecting said chambers, a blower adapted to establish a closed circuit of air mixture successively through the soda, lime chamber and the cooling chamber, a partition forming a passageway opening at the top and bottom of said soda lime chamber to permit bypassing of part of said gas mixture to recirculate through the soda limeA chamber, and a damper in the opening between the soda lime chamber and the cooling chamber for determining the amount of said recirculation.

4. An air-conditioner for therapeutic purposes embodying a soda lime chamber and a cooling chamber withy an opening connecting said chambers, a blower adapted to establish a closed circuit of air mixture successively through the soda lime chamber and the cooling chamber, a partition forming a passageway opening at the top and bottom of said soda lime chamber to permit by-passing of part of said gas mixture to recirculate through the soda lime chamber, a damper in the opening between the soda lime chamber and the cooling chamber for determining the amount of said recirculation, and means for setting the damper to fix the amount of said recirculation as so determined.

5. An air-conditioner for therapeutic purposes embodying a soda lime chamber and a cooling chamber with an opening connecting said chambers, a blower adapted to establish a closed circuit of air mixture successively through the soda lime chamber and the cooling chamber, and means for by-passing some of said air mixture to cause'it to recirculate through the soda lime chamber, said means including means to determine and regulate the amount of said air mixture so by-passed.

6. An air-conditioner for therapeutic purposes embodying a soda lime chamber and a cooling chamber with an opening connecting said chambers, a, blower adapted to establish a closed circuit of air mixture successively through the soda lime chamber and the cooling chamber, a partition forming a passageway opening at the top and bottom of said soda lime chamber to permit bypassing of part of said gas mixture to recirculate through the soda lime chamber, a damper in the opening between the soda lime chamber and the cooling chamber for determining the amount of said recirculation, a handle outside of said casing for moving said damper, and a detent scale cooperating with said handle to iix the damper for e'ecting the amount of said recirculation as so determined.

JAY A. HEIDBRINK. 

